document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=63791>Question 63791</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Solve this word problem.  The cost of 1000 cubic feed of natural gas is $39 and the cost of 3000 cubic feet is $99.  There is a linear equation that expresses the cost C in terms of the number of cubic feet n.  Find the equation and find the cost of 2400 cubic feet of natural gas.\r<BR>\n" );
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document.write( "Please explain the procedure you used to solve this problem.\r<BR>\n" );
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document.write( "Thank you. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #46234 by </B><A HREF=/tutors/aboutme.mpl?userid=venugopalramana><B>venugopalramana(3286)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=venugopalramana><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.geocities.com/venugopalramana/FREE_MATHS_ASSISTANCE.html valign=middle><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=46234\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Solve this word problem. The cost of 1000 cubic feed of natural gas is $39 and the cost of 3000 cubic feet is $99. There is a linear equation that expresses the cost C in terms of the number of cubic feet n. Find the equation and find the cost of 2400 cubic feet of natural gas. <BR>\n" );
document.write( "Please explain the procedure you used to solve this problem. <BR>\n" );
document.write( "Thank you.<BR>\n" );
document.write( "LET COST OF GAS C BE RELATED TO QUANTITY Q BY THE LINEAR RELATION <BR>\n" );
document.write( "C=A*Q+B.WHERE A AND B ARE CONSTANTS TO BE FOUND.<BR>\n" );
document.write( "WEW HAVE C=39$ WHEN Q=1000 CUF  AND  C=99$ WHEN Q = 3000 CUF.SO<BR>\n" );
document.write( "1000A+B=39................1<BR>\n" );
document.write( "3000A+B=99...................2<BR>\n" );
document.write( "EQN.2 - EQN.1<BR>\n" );
document.write( "3000A+B-1000A-B=99-39<BR>\n" );
document.write( "2000A=60<BR>\n" );
document.write( "A=60/2000=3/100=0.03<BR>\n" );
document.write( "PUTTING IN EQN.1<BR>\n" );
document.write( "1000*0.03+B=39<BR>\n" );
document.write( "30+B=39<BR>\n" );
document.write( "B=39-30=9<BR>\n" );
document.write( "HENCE <BR>\n" );
document.write( "C=0.03Q+9 IS THE LINEAR RELATION </SPAN>\n" );
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